Light-emitting device and image display device

Abstract

A light-emitting device according to one embodiment of the present disclosure comprises: a substrate; a first light-emitting element and a second light-emitting element that are provided on the substrate so as to be adjacent to each other; and an embedded layer that is embedded in at least one section between the first light-emitting element and the second light-emitting element and has a higher thermal conductivity than the thermal conductivity of the substrate.

Description

Light-emitting device and image display device

[0001] The present disclosure relates to a light-emitting device and an image display device including the light-emitting device.

[0002] To date, a light emitting device has been proposed in which a plurality of light emitting elements, each including a compound semiconductor layer, are bonded to a substrate having a drive circuit for driving the plurality of light emitting elements (see, for example, Patent Document 1).

[0003] International Publication No. 2022 / 185976

[0004] Recently, there has been a demand for light emitting devices that are capable of stable light emitting operation.

[0005] Therefore, a light emitting device with excellent operational reliability is desired.

[0006] A light-emitting device according to one embodiment of the present disclosure includes a base, a first light-emitting element and a second light-emitting element respectively disposed adjacent to each other on the base, and an embedded layer embedded at least partially between the first light-emitting element and the second light-emitting element, the embedded layer having a thermal conductivity higher than that of the base.

[0007] In a light-emitting device according to one embodiment of the present disclosure, an embedded layer having a thermal conductivity higher than that of the base is disposed at least partially between the first light-emitting element and the second light-emitting element, so that heat generated in the light-emitting element is efficiently transferred to the embedded layer.

[0008] FIG. 1 is a cross-sectional view schematically illustrating an example of a configuration of a light-emitting device according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view schematically illustrating an example of a manufacturing process for the light-emitting device shown in FIG. 1. FIG. 3 is a cross-sectional view schematically illustrating a manufacturing process for the light-emitting device shown in FIG. 1 subsequent to FIG. 2. FIG. 4 is a cross-sectional view schematically illustrating a manufacturing process for the light-emitting device shown in FIG. 1 subsequent to FIG. 3. FIG. 5 is a cross-sectional view schematically illustrating a manufacturing process for the light-emitting device shown in FIG. 1 subsequent to FIG. 4. FIG. 6 is a cross-sectional view schematically illustrating a manufacturing process for the light-emitting device shown in FIG. 1 subsequent to FIG. 5. FIG. 7 is a cross-sectional view schematically illustrating a manufacturing process for the light-emitting device shown in FIG. 1 subsequent to FIG. 6. FIG. 8 is a cross-sectional view schematically illustrating an example of a configuration of a light-emitting device according to Modification 1 of the present disclosure. FIG. 9 is a cross-sectional view schematically illustrating an example of a configuration of a light-emitting device according to Modification 2 of the present disclosure. FIG. 10 is a cross-sectional view schematically illustrating a manufacturing process for the light-emitting device shown in FIG. 9 subsequent to FIG. 4. FIG. 11 is a cross-sectional view schematically illustrating an example of a configuration of a light-emitting device according to Modification 3 of the present disclosure. FIG. 12 is a perspective view illustrating an example of a configuration of an image display device according to an application example of the present disclosure. FIG. 13 is a perspective view illustrating another example of the configuration of an image display device according to an application example of the present disclosure.

[0009] An embodiment of the present disclosure will be described in detail below with reference to the drawings. The following description is one specific example of the present disclosure, and the present disclosure is not limited to the following embodiment. Furthermore, the present disclosure is not limited to the arrangement, dimensions, dimensional ratios, etc. of each component shown in each drawing. The order of description is as follows: 1. One embodiment (example in which a heat dissipation material is provided between light-emitting elements) 1-1. Configuration of light-emitting device 1-2. Method for manufacturing light-emitting device 1-3. Actions and effects 2. Modifications 2-1. Modification 1 (another example of a light-emitting device) 2-2. Modification 2 (another example of a light-emitting device) 2-3. Modification 3 (another example of a light-emitting device) 3. Application examples

[0010] 1 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device 1 according to an embodiment of the present disclosure. The light-emitting device 1 is applicable to, for example, an image display device known as a head-mounted display (for example, a head-mounted display 100 shown in FIG. 11 , which will be described later).

[0011] The light emitting device 1 includes a base 20 extending in, for example, the XY plane, and a light emitting element layer 10 stacked in the Z-axis direction on the base 20. The light emitting element layer 10 includes a plurality of light emitting elements 11 each provided on the base 20 so as to be adjacent to each other in the XY plane.

[0012] (Configuration of Base 20) The base 20 has, for example, a substrate 21 and a wiring layer 22. The wiring layer 22 is provided so as to cover a surface 21US of the substrate 21. A drive circuit 221 that drives the plurality of light-emitting elements 11 is formed on the surface 21US of the substrate 21. As the substrate 21, for example, a single-crystal silicon (Si) substrate can be used.

[0013] The drive circuit 221 includes, for example, a plurality of drive transistors, which may be metal-insulator-semiconductor field-effect transistors (MISFETs) or metal-oxide-semiconductor field-effect transistors (MOSFETs).

[0014] The wiring layer 22 includes an insulating layer 23, a plurality of terminals 24 (24A, 24B), a plurality of wirings 25 (25A, 25B), and a plurality of connection layers 26 (26A, 26B). Note that in FIG. 1 , terminals 24A and 24B are illustrated as examples of the plurality of terminals 24, wirings 25A and 25B are illustrated as examples of the plurality of wirings 25, and connection layers 26A and 26B are illustrated as examples of the plurality of connection layers 26. The insulating layer 23 is formed of an insulating material such as silicon oxide (SiOx), silicon nitride (SiN), or silicon oxynitride (SiON). The upper surfaces of the terminals 24A and 24B are exposed, for example, on the surface 22US of the wiring layer 22. The wirings 25A and 25B are respectively provided between the terminals 24A and 24B and the substrate 21 and are embedded in the insulating layer 23. The connection layers 26A and 26B extend in the Z-axis direction to connect the drive circuit 30 to the wirings 25A and 25B, respectively, and the terminals 24A and 24B, respectively. The terminals 24 and the wirings 25 may be made of a highly conductive material such as aluminum (Al) or copper (Cu). The connection layers 26 may be made of tungsten (W), for example.

[0015] The drive circuit 221 is electrically connected to the terminals 24A and 24B via the connection layers 26A and 26B and the wiring 25A and 25B, respectively.

[0016] (Configuration of Light-Emitting Element Layer 10) The light-emitting element layer 10 includes a plurality of light-emitting elements 11, a plurality of wiring layers 12, a plurality of electrode plugs 13, one or more transparent electrode layers 14, one or more light-reflecting films 15, one or more embedded layers 16, one or more insulating layers 17, one or more insulating layers 18, and one or more insulating layers 19. In FIG. 1 , light-emitting elements 11A and light-emitting elements 11B are illustrated as the plurality of light-emitting elements 11, wiring layers 12A and 12B are illustrated as the plurality of wiring layers 12, and electrode plugs 13A and 13B are illustrated as the plurality of electrode plugs 13. Furthermore, light-reflecting films 15A and 15B are illustrated as the one or more light-reflecting films 15. The light-reflecting films 15A and 15B may be integrally formed.

[0017] Here, light-emitting element 11A corresponds to a specific example of a "first light-emitting element" according to one aspect of the present disclosure, and light-emitting element 11B corresponds to a specific example of a "second light-emitting element" according to one aspect of the present disclosure. Furthermore, wiring layer 12A corresponds to a specific example of a "first wiring layer" according to one aspect of the present disclosure, and wiring layer 12B corresponds to a specific example of a "second wiring layer" according to one aspect of the present disclosure. Furthermore, electrode plug 13A corresponds to a specific example of a "first electrode plug" according to one aspect of the present disclosure, and electrode plug 13B corresponds to a specific example of a "second electrode plug" according to one aspect of the present disclosure. Furthermore, light-reflecting film 15A corresponds to a specific example of a "first light-reflecting film" according to one aspect of the present disclosure, and light-reflecting film 15B corresponds to a specific example of a "second light-reflecting film" according to one aspect of the present disclosure.

[0018] Each of the plurality of light-emitting elements 11 (11A, 11B) is a solid-state light-emitting element that emits light in a predetermined wavelength band from its upper surface, such as an LED (Light Emitting Diode) chip. The LED chip refers to an element cut from a wafer used for crystal growth, and is not a packaged type covered with molded resin or the like. The LED chip has a size of, for example, 2 μm to 100 μm, and is known as a micro LED.

[0019] Each of the plurality of light-emitting elements 11 (11A, 11B) is a light-emitting diode (LED) having a stacked structure in which, for example, a first conductive type first compound semiconductor layer 111 (111A, 111B), an active layer 112 (112A, 112B), and a second conductive type second compound semiconductor layer 113 (113A, 113B) are stacked in this order. Each of the plurality of light-emitting elements 11 (11A, 11B) further includes a first electrode 114 (114A, 114B). The first electrode 114 (114A, 114B) is provided, for example, on the opposite side of the first compound semiconductor layer 111 (111A, 111B) from the active layer 112 (112A, 112B) and is electrically connected to the first compound semiconductor layer 111 (111A, 111B). The first electrodes 114 (114A, 114B) are electrically connected to the wiring layers 12 (12A, 12B) via electrode plugs 13A, 13B, respectively.

[0020] Each of the first compound semiconductor layers 111 (111A, 111B) is formed of, for example, an n-type GaN-based semiconductor material. Each of the active layers 112 (112A, 112B) has a multiple quantum well structure in which, for example, InGaN and GaN are alternately stacked, and has a light-emitting region within the layer. Light in the blue wavelength range of 430 nm to 500 nm, for example, is extracted from each of the active layers 112 (112A, 112B). Light with a wavelength corresponding to, for example, the ultraviolet region (ultraviolet light) may also be extracted from each of the active layers 112 (112A, 112B). Each of the second compound semiconductor layers 113 (113A, 113B) is formed of, for example, a p-type GaN-based semiconductor material. In the light-emitting element 11 (11A, 11B), the upper surface of the second compound semiconductor layer 113 (113A, 113B), i.e., the surface opposite to the active layer 112 (112A, 112B), is the light extraction surface 11S1 of the light-emitting element 11 (11A, 11B).

[0021] Each of the first electrodes 114 (114A, 114B) is in ohmic contact with, for example, each of the first compound semiconductor layers 111 (111A, 111B), and is formed using a transparent conductive material such as a multilayer film (Ni / Au) of nickel (Ni) and gold (Au) or ITO.

[0022] The wiring layers 12 (12A, 12B), electrode plugs 13 (13A, 13B), and insulating layer 18 are provided in a layer between the layer on which the plurality of light-emitting elements 11 (11A, 11B) are provided and the base 20. The wiring layers 12 (12A, 12B) and electrode plugs 13 (13A, 13B) are surrounded by the insulating layer 18. The insulating layer 18 is made of an insulating material such as silicon oxide (SiOx), silicon nitride (SiN), or silicon oxynitride (SiON).

[0023] Each wiring layer 12 (12A, 12B) can supply a predetermined voltage to each light-emitting element 11 (11A, 11B) via each electrode plug 13 (13A, 13B), for example, based on the control of a drive circuit 30. The magnitudes of the voltages applied to each light-emitting element 11 (11A, 11B) may all be the same, or some or all of them may be different. Each wiring layer 12 (12A, 12B) has a layered structure in which, for example, a light-shielding film 122 (122A, 122B) and a light-absorbing film 121 (121A, 121B) are layered in this order.

[0024] Each of the light absorbing films 121 (121A, 121B) absorbs light leaking from between, for example, the light reflecting film 15 (15A, 15B) and the electrode plug 13 (13A, 13B). The light absorbing films 121 (121A, 121B) are formed of a conductive material. The light absorbing films 121 (121A, 121B) are formed of, for example, a single-layer film. The single-layer film may be composed of, for example, a metal or metal compound whose main composition is at least one of titanium nitride (TiN), cobalt (Co), nitrogen-doped titanium oxide (TiON), tantalum nitride (TaN), and amorphous carbon (a-C).

[0025] The light-shielding films 122 (122A, 122B) are disposed on the opposite side of the light-absorbing films 121 (121A, 121B) from the light-emitting elements 11 (11A, 11B). The surface of the light-shielding films 122 (122A, 122B) opposite the light-absorbing films 121 (121A, 121B) is electrically connected to the terminals 24A, 24B of the base 20. The light-shielding films 122 (122A, 122B) are optical films that block leaked light emitted from the light-emitting elements 11 (11A, 11B) and also serve as paths through which electricity flows. In other words, the light-shielding films 122 (122A, 122B) electrically connect the electrode plugs 13 (13A, 13B) to the terminals 24A, 24B. The light-shielding film 122 (122A, 122B) is formed of a single layer film of metal containing, as a main component, at least one of aluminum (Al), copper (Cu), tungsten (W), and titanium (Ti), for example.

[0026] The electrode plugs 13 (13A, 13B) electrically connect the first electrodes 114 (114A, 114B) and the light absorbing films 121 (121A, 121B). The electrode plugs 13 (13A, 13B) are made of, for example, tungsten (W).

[0027] The transparent electrode layer 14 is disposed on the light extraction surface S11 (S11A, S11B), which is the surface of the second compound semiconductor layer 113 (113A, 113B). The transparent electrode layer 14 is provided in common to the plurality of light emitting elements 11 (11A, 11B).

[0028] The light-reflecting films 15 (15A, 15B) are provided so as to surround the periphery of the light-emitting element 11 (11A, 11B). Specifically, the light-reflecting films 15 (15A, 15B) are provided along the side surfaces of the first compound semiconductor layers 111 (111A, 111B), the side surfaces of the active layers 112 (112A, 112B), the side surfaces of the second compound semiconductor layers 113 (113A, 113B), and the surfaces of the first electrodes 114 (114A, 114B) that face the wiring layer 12. An insulating layer 17 is provided between the light-emitting element 11 (11A, 11B) and the light-reflecting films 15 (15A, 15B). The light-reflecting films 15 (15A, 15B) are not provided at positions corresponding to the light extraction surfaces S11 (S11A, S11B). Each of the light-reflecting films 15 (15A, 15B) reflects light emitted from each of the light-emitting elements 11 (11A, 11B) to improve the light extraction efficiency of the light-emitting elements 11 (11A, 11B). The light-reflecting films 15 (15A, 15B) are made of a metal such as aluminum (Al) or tungsten (W) or a metal compound.

[0029] The embedding layer 16 is disposed so as to fill the gaps between adjacent light-emitting elements 11 (11A, 11B). The embedding layer 16 has a thermal conductivity higher than that of the base 20 (the thermal conductivity of the substrate 21 and the thermal conductivity of the wiring layer 22). The embedding layer 16 may include at least one of a metal and a resin containing a metal filler. Examples of the metal or metal filler contained in the embedding layer 16 include aluminum (Al), cobalt (Co), tungsten (W), copper (Cu), silver (Ag), and gold (Au). The embedding layer 16 may include a portion having a length equal to or greater than half the distance between two adjacent light-emitting elements 11 in the arrangement direction of the light-emitting elements 11. For example, as shown in FIG. 1 , in the X-axis direction in which the light-emitting elements 11A and 11B are arranged, the embedding layer 16 includes a portion having a length L16 equal to or greater than half the distance D11 between the light-emitting elements 11A and 11B. That is, it is desirable that the maximum length L16 of the buried layer 16 is greater than the distance D11.

[0030] The insulating layer 17 is provided to surround the periphery of the light-emitting elements 11 (11A, 11B). Specifically, the insulating layer 17 is provided along the side surfaces of the first compound semiconductor layers 111 (111A, 111B), the side surfaces of the active layers 112 (112A, 112B), the side surfaces of the second compound semiconductor layers 113 (113A, 113B), and the surfaces of the first electrodes 114 (114A, 114B) facing the wiring layer 12. The insulating layer 17 is formed of an insulating material such as silicon oxide (SiOx), silicon nitride (SiN), or silicon oxynitride (SiON). The insulating layer 19 occupies a region of the layer in which the light-emitting elements 11 (11A, 11B) are provided, excluding, for example, the regions between the light-emitting elements 11. The insulating layer 19 is also made of an insulating material such as silicon oxide (SiOx), silicon nitride (SiN), or silicon oxynitride (SiON).

[0031] 1-2. Method for Manufacturing Light-Emitting Device The light-emitting device 1 of this embodiment can be manufactured, for example, as follows: Figures 2 to 7 show an example of a manufacturing process for the light-emitting device 1.

[0032] First, the second compound semiconductor layer 113, the active layer 112, and the first compound semiconductor layer 111 are epitaxially grown in this order on a growth substrate such as a sapphire substrate. Next, a conductive film, for example, is formed on the first compound semiconductor layer 111 by, for example, vapor deposition, and then the conductive film is selectively removed by lift-off. In this way, a plurality of first electrodes 114 having a predetermined planar shape are formed.

[0033] Subsequently, after the growth substrate is peeled off, the transparent electrode layer 14 is formed so as to be in contact with the second compound semiconductor layer 113. The transparent electrode layer 14 is obtained by depositing indium tin oxide using, for example, a sputtering method or a vapor deposition method. The deposited transparent electrode layer 14 may be processed into a predetermined shape by a wet etching process.

[0034] 2 , the first compound semiconductor layer 111, the active layer 112, and the second compound semiconductor layer 113 in predetermined regions are selectively removed by, for example, dry etching to form a plurality of recesses U. As a result, a plurality of light-emitting elements 11 are obtained.

[0035] 3 , an insulating layer 17 is formed so as to cover the light emitting element 11, i.e., so as to cover the side surfaces of the first compound semiconductor layer 111, the active layer 112, the second compound semiconductor layer 113, the surface of the first electrode 114, and the surface of the transparent electrode layer 14. After the insulating layer 17 is formed, a light reflective film 15 is formed on the insulating layer 17. The light reflective film 15 can be formed by, for example, chemical vapor deposition or atomic layer deposition.

[0036] 4, an insulating layer 19 is embedded in the recess U in contact with the light-reflecting film 15. Thereafter, the surface of the insulating layer 19 is planarized by, for example, CMP (Chemical Mechanical Polishing) to expose the light-reflecting film 15. The insulating layer 19 is formed from an insulating material such as silicon oxide (SiOx), silicon nitride (SiN), or silicon oxynitride (SiON).

[0037] Next, as shown in FIG. 5 , a mask layer M is provided to cover the surface of the light-emitting element 11 covered with the light-reflecting film 15 and the insulating layer 19. The mask layer M is a hard mask formed using, for example, polysilicon, a metal silicide such as tungsten silicide, a metal, a metal compound, or the like. Alternatively, the mask layer M may be formed by, for example, ion implantation using a resist. The mask layer M has openings MK at predetermined positions corresponding to some of the recesses U. The openings MK are formed by, for example, dry etching. Next, a portion of the insulating layer 19 is selectively removed by dry etching using the mask layer M as a mask, exposing a portion of the light-reflecting film 15 in the recesses U.

[0038] Next, after removing the mask layer M, as shown in Fig. 6, the embedded layer 16 is formed so as to cover the light emitting element 11 covered with the light reflecting film 15 and the insulating layer 19. At this time, the embedded layer 16 is formed so as to be embedded in the exposed recess U.

[0039] 7, the portions of the embedded layer 16 other than the portion filling the recess U are removed. After that, the portion of the light-reflecting film 15 in contact with the first electrode 114 is selectively removed. An electrode plug 13 is provided in contact with the exposed first electrode 114 and connected to the wiring layer 12. This completes the light-emitting device 1 shown in FIG.

[0040] [1-3. Effects of the Light-Emitting Device] In the light-emitting device 1 of the present embodiment, light generated in each of the plurality of light-emitting elements 11 is emitted from the light extraction surface S11 under the control of the drive circuit 30 provided on the base 20. When each of the plurality of light-emitting elements 11 generates light, heat is generated from the plurality of light-emitting elements 11. If heat accumulates inside the light-emitting device 1, it may cause malfunction of the drive circuit 30 or affect reliability. Therefore, in the light-emitting device 1 of the present embodiment, an embedding layer 16 having a thermal conductivity higher than that of the base 20 is embedded at least partially between adjacent light-emitting elements 11. This allows heat generated in the light-emitting elements 11 to be efficiently transferred to the embedding layer 16. As a result, in the light-emitting device 1 of the present embodiment, heat generated when the light-emitting elements 11 emit light is efficiently dissipated to the outside of the light-emitting device 1.

[0041] Therefore, according to the light emitting device 1 of this embodiment, even when it is equipped with a plurality of highly integrated light emitting elements 11, stable light emitting operation is possible, and excellent operational reliability can be ensured.

[0042] 2. Modifications Next, modifications 1 to 3 and application examples of the present disclosure will be described. Note that components corresponding to those in the light emitting device 1 of the above embodiment will be assigned the same reference numerals and descriptions thereof will be omitted.

[0043] [2-1. Modification 1] FIG. 8 is a cross-sectional view that schematically illustrates an example of the cross-sectional configuration of a light-emitting device (light-emitting device 2) according to Modification 1 of the present disclosure.

[0044] The light emitting device 2 further includes a dummy electrode plug 43 and a dummy wiring layer 42. The embedded layer 16 is connected to the dummy wiring layer 42 via the dummy electrode plug 43. Except for this, the configuration of the light emitting device 2 is substantially the same as that of the light emitting device 1 of the above embodiment. The dummy electrode plug 43 and the dummy wiring layer 42 may be made of the same material as the electrode plug 13 and the wiring layer 12, respectively. In addition, an insulating layer 18 may be filled around the dummy electrode plug 43 and the dummy wiring layer 42. The wiring layer 12 and the dummy wiring layer 42 of the light emitting element 11 may be provided at the same layer.

[0045] Here, the dummy wiring layer 42 corresponds to a specific example of a "dummy wiring layer" according to one aspect of the present disclosure, and the dummy electrode plug 43 corresponds to a specific example of a "dummy electrode plug" according to one aspect of the present disclosure.

[0046] By providing the dummy electrode plug 43 and the dummy wiring layer 42, the heat transferred from the light emitting element 11 to the embedded layer 16 can be dissipated to the outside of the light emitting device 2 more efficiently.

[0047] [2-2. Modification 2] FIG. 9 is a cross-sectional view that schematically illustrates an example of the cross-sectional configuration of a light-emitting device (light-emitting device 3) according to Modification 2 of the present disclosure.

[0048] In the light emitting device 3, the embedded layer 16 has an insulating film 161 and a conductive film 162. Except for this, the configuration of the light emitting device 3 is substantially the same as the configuration of the light emitting device 1 of the above embodiment. In the light emitting device 3, a first region R1 having a first width W1 in the X-axis direction and a second region R2 having a second width W2 in the X-axis direction that is wider than the first width W1 are present between the light emitting elements 11A and 11B. Here, the first region R1 is occupied by the insulating film 161, and the second region R2 is occupied by the conductive film 162.

[0049] The insulating film 161 is made of an insulating material such as silicon oxide (SiOx), silicon nitride (SiN), or silicon oxynitride (SiON).

[0050] The conductive film 162 includes at least one of a metal and a resin having a metal filler, such as aluminum (Al), cobalt (Co), tungsten (W), copper (Cu), silver (Ag), or gold (Au), or is formed using a resin material having a metal filler.

[0051] The light emitting device 3 can be manufactured in the same manner as the light emitting device 1 up to the stage of forming the mask layer M. As shown in Fig. 10, a portion of the insulating layer 19 is selectively removed using the mask layer M to form a recess UA. The insulating layer 19 remaining in the recess U at this time serves as an insulating film 161. After a conductive film 162 is formed to fill the recess UA and a buried layer 16 is obtained, the light emitting device 3 is formed in the same manner as the light emitting device 1.

[0052] [2-3. Modification 3] FIG. 11 is a cross-sectional view that schematically illustrates an example of the cross-sectional configuration of a light-emitting device (light-emitting device 4) according to Modification 3 of the present disclosure.

[0053] In the light emitting device 4, an insulating film 51 and a light absorbing film 50 are further provided between the light reflecting film 15 and the embedded layer 16. Except for this, the configuration of the light emitting device 4 is substantially the same as the configuration of the light emitting device 1 of the above embodiment.

[0054] The insulating film 51 is provided along and overlapping the light reflecting film 15. The insulating film 51 is made of an insulating material such as silicon oxide (SiOx), silicon nitride (SiN), or silicon oxynitride (SiON).

[0055] The light absorbing film 50 is provided along the insulating film 51, between the insulating film 51 and the buried layer 16. The light absorbing film 50 is made of a material having light absorbing properties. The light absorbing film 50 may be made of an insulating material such as silicon oxide (SiOx), silicon nitride (SiN), or silicon oxynitride (SiON). Alternatively, the light absorbing film 50 may be made of a resin material.

[0056] 12 is a perspective view showing an example of the appearance of an image display device (head-mounted display 100) using a light-emitting device (e.g., light-emitting device 1) according to the present disclosure. The head-mounted display 100 has, for example, a glasses-shaped display unit 120 and ear hooks 122 on both sides of the glasses-shaped display unit 120 for wearing on the user's head. The light-emitting device (e.g., light-emitting device 1) according to the present disclosure can be used for the display unit 120.

[0057] (Application Example 2) FIG. 13 is a perspective view illustrating another example (head-mounted display 200) of the appearance of an image display device using a light-emitting device (e.g., light-emitting device 1) according to the present disclosure. The head-mounted display 200 is a so-called see-through head-mounted display and includes a main body 221, an arm 222, and a lens barrel 223. The head-mounted display 200 is attached to, for example, eyeglasses 224. The main body 221 includes a control board and a display unit for controlling the operation of the head-mounted display 200. The display unit emits image light of a display image, and may include a light-emitting device (e.g., light-emitting device 1) according to the present disclosure. The arm 222 connects the main body 221 and the lens barrel 223 and supports the lens barrel 223. The lens barrel 223 projects the image light supplied from the main body 221 via the arm 222 toward the user's eyes via lenses 225 of the eyeglasses 224.

[0058] The present disclosure has been described above with reference to the embodiment, modified examples 1 to 3, and application examples, but the present disclosure is not limited to the above-described embodiment, etc., and various modifications are possible. For example, in the above-described embodiment, etc., examples have been shown in which the light emitted from the light-emitting element 11 is blue light or ultraviolet light, but the present disclosure is not limited to this. For example, the light-emitting device 1 may also use a light-emitting element that emits two or more types of light, such as blue light and green light, or ultraviolet light and green light.

[0059] Furthermore, in the above embodiments, each component constituting the light emitting device 1 etc. has been specifically listed and described, but it is not necessary to include all components, and other components may also be included.

[0060] Furthermore, the above modifications 1 to 3 can be combined with each other in any way.

[0061] A light-emitting device according to one embodiment of the present disclosure includes a base, a first light-emitting element and a second light-emitting element disposed adjacent to each other on the base, and a buried layer embedded at least partially between the first light-emitting element and the second light-emitting element, the buried layer having a thermal conductivity higher than that of the base. This allows heat generated in the light-emitting element to be efficiently transferred to the buried layer, thereby enabling stable light-emitting operation. Note that the effects described herein are merely examples and are not intended to be limiting, and other effects may also be present.

[0062] The present disclosure may also be configured as follows: (1) A light-emitting device comprising: a base; a first light-emitting element and a second light-emitting element respectively provided adjacent to each other on the base; and an embedding layer embedded at least partially between the first light-emitting element and the second light-emitting element, the embedding layer having a thermal conductivity higher than that of the base. (2) The light-emitting device according to (1) above, wherein, in an arrangement direction in which the first light-emitting element and the second light-emitting element are aligned, the embedding layer includes a portion having a length equal to or greater than half the distance between the first light-emitting element and the second light-emitting element. (3) The light-emitting device according to (1) or (2) above, wherein the embedding layer includes at least one of a metal and a resin containing a metal filler. (4) The light-emitting device according to any one of (1) to (3) above, wherein each of the first light-emitting element and the second light-emitting element includes a stacked structure in which a first compound semiconductor layer of a first conductivity type, an active layer, and a second compound semiconductor layer of a second conductivity type are stacked in this order. (5) The light-emitting device according to (4), further comprising: a first electrode plug connected to the first light-emitting element; a first wiring layer connected to the first electrode plug and supplying a first voltage via the first electrode plug; a second electrode plug connected to the second light-emitting element; and a second wiring layer connected to the second electrode plug and supplying a second voltage via the second electrode plug. (6) The light emitting device according to (5), further comprising a first light reflecting film and a second light reflecting film, wherein the first light reflecting film extends along a side surface of the first compound semiconductor layer, a side surface of the active layer, a side surface of the second compound semiconductor layer, and a surface of the second compound semiconductor layer facing the first wiring layer in the first light emitting element, and reflects light emitted from the first light emitting element, and the second light reflecting film extends along a side surface of the first compound semiconductor layer, a side surface of the active layer, a side surface of the second compound semiconductor layer, and a surface of the second compound semiconductor layer facing the first wiring layer in the second light emitting element, and reflects light emitted from the second light emitting element.(7) The light-emitting device according to any one of (1) to (6) above, wherein the metal contained in the buried layer is at least one of Al (aluminum), Co (cobalt), W (tungsten), Cu (copper), Ag (silver), and Au (gold). (8) The light-emitting device according to (5) above, further comprising a dummy electrode plug and a dummy wiring layer, wherein the buried layer is connected to the dummy wiring layer via the dummy electrode plug. (9) The light-emitting device according to (8) above, wherein the first wiring layer, the second wiring layer, and the dummy wiring layer are provided in the same layer. (10) The light-emitting device according to any one of (1) to (9), wherein the embedded layer has an insulating film and a conductive film, and between the first light-emitting element and the second light-emitting element, there are present a first region having a first width in an arrangement direction in which the first light-emitting element and the second light-emitting element are arranged, and a second region having a second width in the arrangement direction that is wider than the first width, and the first region is occupied by the insulating film, and the second region is occupied by the conductive film. (11) An image display device comprising a light-emitting device, the light-emitting device having: a base; a first light-emitting element and a second light-emitting element provided adjacent to each other on the base; and an embedded layer embedded at least partially between the first light-emitting element and the second light-emitting element, the embedded layer having a thermal conductivity higher than that of the base.

[0063] This application claims priority based on Japanese Patent Application No. 2023-129911, filed on August 9, 2023, in the Japan Patent Office, the entire contents of which are incorporated herein by reference.

[0064] Those skilled in the art will recognize that various modifications, combinations, subcombinations, and variations may occur depending on design requirements and other factors, and are intended to be within the scope of the appended claims and their equivalents.

Claims

1. A light emitting device comprising: a base; a first light emitting element and a second light emitting element each provided adjacent to each other on the base; and an embedding layer embedded at least partially between the first light emitting element and the second light emitting element, the embedding layer having a thermal conductivity higher than that of the base.

2. The light emitting device according to claim 1, wherein in an arrangement direction in which the first light emitting element and the second light emitting element are arranged, the embedded layer includes a portion having a length equal to or greater than half the distance between the first light emitting element and the second light emitting element.

3. The light emitting device according to claim 1, wherein the embedding layer contains at least one of a metal and a resin having a metal filler.

4. The light-emitting device according to claim 1, wherein each of the first light-emitting element and the second light-emitting element includes a laminated structure in which a first compound semiconductor layer of a first conductivity type, an active layer, and a second compound semiconductor layer of a second conductivity type are laminated in that order.

5. The light-emitting device according to claim 4, further comprising: a first electrode plug connected to the first light-emitting element; a first wiring layer connected to the first electrode plug and supplying a first voltage via the first electrode plug; a second electrode plug connected to the second light-emitting element; and a second wiring layer connected to the second electrode plug and supplying a second voltage via the second electrode plug.

6. The light-emitting device according to claim 5, further comprising a first light-reflecting film and a second light-reflecting film, wherein the first light-reflecting film extends along a side surface of the first compound semiconductor layer, a side surface of the active layer, a side surface of the second compound semiconductor layer, and a surface of the second compound semiconductor layer facing the first wiring layer in the first light-emitting element, and reflects light emitted from the first light-emitting element, and the second light-reflecting film extends along a side surface of the first compound semiconductor layer, a side surface of the active layer, a side surface of the second compound semiconductor layer, and a surface of the second compound semiconductor layer facing the first wiring layer in the second light-emitting element, and reflects light emitted from the second light-emitting element.

7. The light emitting device according to claim 1, wherein the metal contained in the buried layer is at least one of Al (aluminum), Co (cobalt), W (tungsten), Cu (copper), Ag (silver), and Au (gold).

8. The light emitting device according to claim 5, further comprising a dummy electrode plug and a dummy wiring layer, said buried layer being connected to said dummy wiring layer via said dummy electrode plug.

9. The light emitting device according to claim 8, wherein the first wiring layer, the second wiring layer, and the dummy wiring layer are provided at the same level.

10. The light-emitting device according to claim 1, wherein the embedded layer has an insulating film and a conductive film, and between the first light-emitting element and the second light-emitting element, there is a first region having a first width in an arrangement direction in which the first light-emitting element and the second light-emitting element are arranged, and a second region having a second width in the arrangement direction that is wider than the first width, the first region being occupied by the insulating film, and the second region being occupied by the conductive film.

11. An image display device comprising a light-emitting device, the light-emitting device having a base, a first light-emitting element and a second light-emitting element provided adjacent to each other on the base, and an embedding layer embedded at least partially between the first light-emitting element and the second light-emitting element, the embedding layer having a thermal conductivity higher than that of the base.

Images